Screw-machine.



Patented Dec. '2, I902.

F. E. WELLS.

SCREW MACHINE. (Applicatiqn filed June so; 1902.)

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(in Model.)

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r. E. WELLS.

SCREW MAGHINE.

(Application filer! June 30, 1902. (No Model.) 3 Sheets-Sheet 2 W277? 68666 r lfivntor Jim-neg? m. 7|4,s4|. Patented Dec. 2. I902.

F. E WELLS. SCREW MACHINE.

(Appliuation filed June 30, 1902-) (No Model.) 3 Sheets-Sheat 3.

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FREDERIC E. WELLS, OF GREENFIELD, MASSACHUSETTS.

SCREW-MACHINE.

SPECIFICATION forming part of Letters Patent No(. 714,841, dated December 2, 1902. Application filed June 30,1902. Serial No- 113,866. (No model.)

To (LZZ whom, it may concern.-

Be it known that I, FREDERIC E. WELLS, a citizen of the United States of America, residing at Greenfield, in the county of Franklin and State of Massachusetts, have invented new and useful Improvements in Screw-Machines, of which the following is a specification.

This invention relates to screw-machines and analogous constructions, and has particular reference to mechanism for operating the tool-turret of such machines, the object of the invention being to provide in this class of machines a turret-feed operated at will in either direction, either by fluid-pressure or interchangeably by a screw-feed, and in the provision of means whereby the turret when operated by fluid-pressure may be so operated at any desired rate of speed, or at one rate of speed in one direction and at a different rate in the opposite direction.

In the drawings forming part of this application, Figure 1 is a longitudinal elevation, partly in section, of a machine embodying my invention. Fig. 2 is an enlarged transverse section on line 2 2, Fig. 1. Figs. 3 and 4 are perspective views of mechanism whereby the turret and turret-operating devices are operatively connected. Fig. 5 is a transverse section through the valve, whereby the flow of fluid to and from the turret-operating devices is controlled.

This invention is particularly applicable and is shown applied to a screw-machine having a cylindrical turret-slide, such as is shown in my patent of November 20, 1900, No. 662,209. In the drawings this turret-slide is indicated by a and is suitably supported on the frame of the machine. It is in the form of a hollow cylinder, and the outer end there of may or may not be supported by a vertical frame, as shown. In machines adapted to small work such support is unnecessary. The turret is indicated by b and is in the form of a ring having a hub-like projection 0 thereon, whereby a suitable bearing on the turretslide is provided, and to this projection the turret-rotating devices are secured. These will be described farther on. At the various points about the periphery of the annular turret at which the tool-chucks are mounted there are formed radially-disposed bosses or projections d, (shown in Fig. 2,) which preferably are integral with the turret and Whose outersurfaces areconcentric therewith. These tool-chucks are indicated by e and are capable of a circumferential adjustment to a slight extent and in their adjusting movement may slide on a circumferentially-disposed gib f and are secured to the turret by bolts g. The tool-holding element on the stud is herein shown in the form of a split sleeve. This, however, is a mere matter of choice, as the tools may be secured to the chucks in any way found desirable.

The turret-rotating devices consist of a wheel h, secured to the hub c of the turret, and between the hub of this wheel and the end of the hub of the turret there is an annular groove t, which is shown in Fig. 1 partly in full lines and partly in dotted lines. On opposite sides of the turret-slide there is a slotj, parallel with the axis of the slide, and a cross-head 70 (shown in Fig. 3) is located in said turret-slide transversely thereof, the ends of which project through the slots j and into the annular groove t', by which connection is made with the turret, of such a nature, however, that while the latter may revolve at will on the turret-slide a it may be moved in either direction on said slide by means of this connection with the cross-head. This is apparent by a glance at Fig. 3, which shows the relation of the parts in their operative position. The cross-head 70 within the turrot-slide a is connected with the turret-feed ing devices, as will be hereinafter described. Suffice it for the moment to say that by means of these devices the turret and the wheel h are moved longitudinally of the slide.

Means for rotating the turret consistin an arm m, bolted to the wheel h and extending rearwardly therefrom near the surface of the slide. Secured non-rotatably upon the slide there is a sleeve n, having on the surface thereof cam-grooves 0 ,of such contour that when the turret runs backward away from the work and the arm m engagesone of these cam-grooves 0 the turret will thereby be ro-' tated to a degree equal to half the distance between two of the tool-chucks, and when the turret goes forward again toward the work the other half of its rotational movementwill be imparted thereto by the engagement of the arm m with another cam-groove having theproperconformation. Toinsuretheguiding of the arm m in the proper direction, there is a swiveled sheep on its end having pointed extremities, as clearly shown in Fig. 1, whereby the proper groove may be engaged to move the turret in the right direction.

The particular form of cam-groove required to give the turret a rotational movement, as above described, is that of the letter Y, laid out with the branch ends thereof toward the rear end of the machine and connected together at the ends thereof. Thus when the sheep on the end of the arm on enters one of these Y-shaped grooves if the shoe has its extremity beveled, as shown in Fig. 1, it will always engage that branch of the Y-groove which will carry the turret away from the observer as the parts are seen in Fig. 1. If, however, the shoe p be reversed, then the backward and forward movements thereof in said Y-grooves will impart to the turret rotational movementin theoppositedirection. Thusfar there has been nothing described in this construction which provides for holding the turret against rotation during its operative movement toward and in contact with the work. Such a device, however, is provided for and is shown in side and end elevation in Figs. 1 and 2, and it is constructed as follows: There extends between the standard of the machine and the frame part which supports the outer end of the turret-slide a trough q, in which oil and chips which may drop from the machine are caught. On one edge of this trough the metal is thickened sufficiently to permit planing out therein a slideway for mounting therein a plate r. The latter is considerably shorter than the slideway in which it moves, and it may be secured therein'by screws .9 or otherwise in any desired position. The plate 1' is milled out to receive the guide-bar 25, which is of substantially the same length of the plate in which it rests and is movable in and out of said slot by means of two arms u, pivoted, as shown in Fig.2, on the plate 1' and engaging by pin-and-slot connection the ends of the bar 6. The free ends of the arms to are united by a rod 12. Said bar If rests on spiral springs 10, whereby it is pressed outwardly.

The location of the above-described parts is such that the bar 15 will have a movement radial to the axis of the turret-slide. In the periphery of the wheel h, which is attached to the hub c of the turret, there are notches 00, with which the edgev of the bar twill engage when the turret and the wheel h are revolved, and when so engaged by said bar a tool is brought into proper operative position relative to work held in the chuck y. This chuck is mounted on a spindle 2, provided with drivingpulley 3, all as usually constructed in this class of machine. When the rim of the wheel It has been engaged, as just described, by the bar t, then the movements of the turret back and forth on the slide a, are guided bythe engagement of said wheel with said bar 6. Means are providedas the screw 4, for exam ple-whereby the bar 25 may be securely locked in or out of engagement with the rim of the Wheel h. The springs w will in ordinary usage hold the bar in engagement with the notches in the wheel h. In their proper operative relation the plate r is so located that the Wheel h during the forward movement of the turret may not become disengaged from the bar 23; but upon the movement of the turret in the opposite direction the wheel 77. will run off the end of the bar 15 just after the shoe 1) on the arm 121 has entered the straight portion of one of the cam-slots 0. Thus the wheel h is never free to be revolved by hand on the slide unless the bar t is held out of engaging position therewith.

It is obvious that the spacing of the slots at: about the periphery of the wheel 71 must be identical with the spacing of the tool-chucks 6 about the periphery of the turret.

The feed mechanism for the turret may, as has already been described, be derived from two sourcesviz., a screw-feed or a feed operated by fluid pressure. Fluid pressure feed for the turret is provided by locating a cylinder5 in the frame of the machine in axial alinement with the turret-slide and providing therein'a piston-head 6, from which there extends through the usual stuffing-box in the end of the cylinder a piston-rod 7, which is screwed into or otherwise secured in a boss 8 on the'cross-head k, as shown in Figs. 1 and 3. The cylinder is entered at either end thereof by a pipe 9, in which there is located a four-way valve 10. Communicating with this valve is a pipe 12, in which there is located a force-pump 13, the suction end of which by a pipe 14 communicates with a reservoir 15, containing some suitable fluid, as oil or water, which by the operation of the pump is forced through the valve 10 into either end of the cylinder, as desired,' the valve 10, of a well-known four-way type, being so constructed that when one end is made to pass under pressure into one end of the cylinder a passage will be opened therethrough, whereby fluid in the opposite end of the cylinder may escape through the wastepipe 16 into said receptacle 15. It is obvious, therefore, that the cylinder 5 will at all times be filled to its full capacity on both sides of the piston-head, whereby great steadiness in the movement of the piston may be attained, and, if necessary, to this end the outlet or waste pipe 16 may be made, if desired, of a slightly-smaller area than the inlet-pipe 12 and the valve-passages. By manipulating the plug of the valve 10 the turret can thus by the means described be moved by the pressure of the fluid against the piston 6 in either direction and at any desired rate of speed. It is desirable, however, at times for certain classes of work that the turret should be provided with a screw-feed, and to this end the piston 6 and the piston-rod 7 are provided with an axial passage therethrough, and a long feed-screw 17 passes through the cylinder, the piston-head, and the piston-rod and also through the cross-head k to the outer end of the turret-slide, at which point it may be rotatably supported. Only so much of the outer end of the feed-screw need be threaded as is requisite to carry the turret to and from the work the required distance. Where this feedscrew enters the cylinder and enters the piston-head 6 sutiable packing-glands 18 are provided to prevent the leak of oil through the piston-rod 7. Enough oil, however, will reach that part of the feed-screw lying within the piston-rod to provide for its proper lubrication. The end of the feed-screw which projects through the head of the cylinder 5 at the end of the machine is connected by suitable gears 19 with the spindle 2 in the same way that such connections are made on other machines of this class for driving a feed-screw. At that point where the feed-screw comes through the cross-head It there is provided means, which are illustrated in Fig. 3 and also on a smaller scale in Fig. 2, whereby the cross-head may be locked to the feed-screw by the engagement with the latter of a nut carried on the cross-head. This nut construction is shown in said Fig. 3 with the parts in separated relation. The construction is as follows: There is cast on the crosshead Isavertically-disposed plate 20, in which the horizontal groove 21 is planed out, which lies at right angles to the feed-screw. In this groove the plate 22 may slide toward and from the feed-screw to cause the engagement with the latter of a nut 23 on said plate 22. This plate may be confined in the groove 21 in any suitable way, as by screwing a strip along each edge of the plate 20, the edges of which shall overlap the edges of the plate. To throw the nut 23 into or out of engagement with the feed-screw, an ear 24 is cast on the plate 22, and another ear 25 is cast on the cross-head, and when the plate 22 is in its proper position these two ears are in alinement, and the screw-threaded end of a pin 26 enters a similarly-threaded hole in the ear 24:, the opposite end of thepin projecting through the ear 25 and being provided withasuitahle head whereby it may be rotated. A collar 27, fixed on the said pin 26, or a flange turned thereon lies between the ears 24 and 25, and thus prevents endwise movement of said pin in one direction, and the head of the pin applied thereto outside of the car 25 likewise prevents endwise movement of the pin in the opposite direction. Thus the plate 22 may be moved up against the feed-screw with any desired degree of force and may be withdrawn from contact therewith at will. The feed-screw would be used generally to drive the turret toward the work only and could not be utilized for the reverse movement of the turret unless means were provided for reversing its rotative movement. Its principal use, however, in connection with this class of machines is for imparting to the turret a known feed movement relative to'the rotation of the work whereby certain screwthreads may be cut as desired. For other work the fluid-pressure feed is to be preferred, and by throwing the nut 23 out of engagement with the feed-screw the fluid-pressure feed may be used exclusively.

Having thus described my invention, what I claim, and desire to secure by Letters Patent of the United States, is

1. In a screw-machine, a tool-turret, a turret-slide, a feed-screw for the latter, and devices for connecting and disconnecting the turret and feed-screw; acylinder, and piston therein, within which said feed-screw is axially located, a tubular piston-rod,through which the feed-screw extends, secured by one end to the turret, and devices for supplying fluid under pressure to said cylinder to move the turret independently of said feed-screw.

2. In a screw-machine, a cylindrical turretslide, an annular tool-turret longitudinally and rotatably movable on the slide, a feedscrew for moving the turret, and devices for connecting and disconnecting the latter from the feed-screw; combined with other turretfeeding devices comprising a cylinder, a piston therein, a tubular piston-rod through which said feed-screw extends, said rod being secured by one end to the turret, and devices for supplying fluid under pressure to said cylinder to move the turret independently of the feed-screw.

FREDERIC E. WELLS.

Witnesses:

WM. 11. OHAPIN, FRED H. GILL. 

